This invention relates generally to improved latching mechanisms for retaining bits in impact type tools. More particularly, this invention relates to an improved latch for an impact tool that inhibits the inadvertent discharge of a bit therefrom when in the unlatched position.
One example of a similar latch is described in U.S. Pat. No. 2,716,393, issued Aug. 30, 1955 to H. R. Fischer. While the latch shown therein is very effective to retain the bit in the tool when in the latched position, the latch is arranged to move to a position where it cannot engage the bit when rotated to the unlatched position. Movement of the latch in this manner facilitates removal and insertion of bits, but the lack of engagement with the bit in the unlatched position can result in the inadvertent, and possibly dangerous, discharge of the bit if the operator fails to rotate the latch to the latched position prior to operating the tool.
An object of this invention is to provide an improved latch for retaining bits in impact type tools. Another object of this invention is to provide an improved latch that positively retains a bit in an impact type tool when in the latched position and that inhibits the discharge of the bit in the event the tool is operated with the latch in the unlatched position.
This invention provides an improved latching mechanism for retaining a bit in an impact-type tool that includes a nose portion having a longitudinally extending opening for receiving the bit and a radially disposed port intersecting the opening, the improvement comprising a latch member extending through the radial port for engaging the bit, the latch member being rotatable therein between latched and unlatched positions; and, resilient means located on the nose portion in engagement with the latch member for preventing inadvertent movement of the latch member from one position to the other and for urging the latch member into frictional engagement with the bit when the latch member is in the unlatched position .